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arXiv · 2505.21619

Valence-bonds, spin liquids and unconventional criticality in a 1D Kondo insulator

Nai Chao Hu·Rui-Zhen Huang·Nick Bultinck
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Abstract

We consider a one-dimensional multi-orbital Kondo lattice model and show that by tuning the kinetic energy of the itinerant electrons it is possible to stabilize Kondo insulators with non-trivial spin physics. In particular, depending on the size of the exchange coupling between the local moments, we find kinetic-energy-driven transitions between a featureless Kondo insulator and a valence-bond solid or a gapless spin liquid. We also provide evidence for an unconventional continuous phase transition between two featureless Kondo insulators distinguished by their quantum numbers under reflection symmetry.

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Nai Chao Hu, Rui-Zhen Huang, Nick Bultinck. 2025-05-27. Valence-bonds, spin liquids and unconventional criticality in a 1D Kondo insulator. https://arxiv.org/abs/2505.21619

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